It is well known to add various metal compounds to vinyl halide polymers for the purpose of inhibiting the degradation that occurs when these polymers are heated during fabrication, e.g., milling, extrusion, molding and calendering. Among the most effective stabilizers are 1) organotin compounds containing one or two. hydrocarbon groups bonded to the tin atom, 2) sulfur-containing antimony compounds, particularly trivalent antimony compounds of the general formula Sb(SR)3 wherein R represents a hydrocarbyl group or the residue remaining following removal of the hydrogen atom from the sulfur atom of a mercaptan or mercaptocarboxylic acid ester, and 3) the alkaline earth metal, zinc, cadmium and lead salts of carboxylic acids. The relatively high cost of these stabilizers, particularly the organotin and antimony compounds, has provided an incentive to search for less expensive materials which can at least partially replace the metal compound without significantly impairing the stability imparted to the vinyl halide polymer.